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Comment: One of these things is not like the other. (Score 1) 112

by DerekLyons (#48639939) Attached to: Ask Slashdot: Resources For Kids Who Want To Make Games?

It's interesting, the asker asks for information about making games and the posters almost universally reply with information about making code. You guys do know these are two completely different activities? (And that computer games are only a small slice of the total gaming universe?)

Comment: Re:$32 million of greed. (Score 1) 166

by DerekLyons (#48639921) Attached to: Calculus Textbook Author James Stewart Has Died

RTFA. It clearly says that it wasn't all from textbook sales but also from "astute investments". Sounds like the guy worked hard and had his shit together financially.

Use some common sense - unless you have Warren Buffet levels of financial acuity or a great deal of luck, you don't accumulate that much cash via investments unless you start with a pile of cash nearly that size.

Comment: Re:Skeptics and Deniers (Score 1) 622

by DerekLyons (#48635317) Attached to: Skeptics Would Like Media To Stop Calling Science Deniers 'Skeptics'

Deniers pretend to be skeptics. However, they are actually exactly the opposite: the distinguishing feature of deniers is not skepticism, but credulity-- they seen to credit pretty much anything they hear (or read on a blog somewhere)-- if it supports their pre-existing opinions.

And how is that different from the True Believer? Very few people who claim to worship at the altar of science behave in any way notably differently - tell 'em it's Science and if it supports their pre-existing opinions they adopt it as Gospel. Many people who claim to respect Science as little better than cargo cultists.

Comment: Re:Established science CANNOT BE QUESTIONED! (Score 1) 622

by DerekLyons (#48635247) Attached to: Skeptics Would Like Media To Stop Calling Science Deniers 'Skeptics'

I use that as an example because it is more clear-cut than the climate issue, where there are a lot of people who hold a spectrum of views which are probably somewhere between being very skeptical and being outright deniers, but for sure there are those who pretty clearly aren't interested in any science that says man-made climate change might be real.

Nobody with any sense denies that such people (those who completely ignore science) exist. The problem is that a lot of people, almost all of which should know better, wants to lump everyone who questions the dogma of climate change in with that minority. Which doesn't actually surprise me, as practically all religions behave that way - dividing the world into Us and Them. And make no mistake, nowadays science *is* a religion, a fetish brandished by many to mark themselves part of the tribe. Like the most fervent bible thumper, they don't really understand the world around them - but the Gospel according to Jaime and the Gospel of St. Niel assures them they are among the smartest and thus among the righteous and the saved.

Comment: Re:Core business? (Score 1) 219

by DerekLyons (#48631501) Attached to: Marissa Mayer's Reinvention of Yahoo! Stumbles

What exactly is Yahoo's "core business"? Their webdirectory is defunct, search outsourced to Bing, and email largely been eaten by its competitors.

They still have a considerable gaming community. Their stock, business, and financial management pages are still top notch. Flickr, despite a couple of recent "hold my beer and watch this" moments is still strong in the photography community... Their front page still draws a huge number of hits.

The problem is less one of Yahoo than it is of hedge fund managers, stock "analysts", and you pretty much knowing nothing of Yahoo's business.

Comment: Re:Missed the Boat by about 15 years (Score 2) 219

by DerekLyons (#48631491) Attached to: Marissa Mayer's Reinvention of Yahoo! Stumbles

Yahoo fantasy football is still about the best around. Same with their sports apps. They bought up Sportstacular and haven't ruined it (it's actually gotten quite better since the acquisition), so those are great.

Yep. And their Stock, business, and financial management pages are top notch too... (to the point where Google has finally given up even trying to compete). Then there's Flickr, which, despite a few missteps, is still the largest and best photographic community out there. Etc... etc...

Yahoo! maybe not be where the cool kids hang out, and it's hasn't been on the tech hipsters hot list for over a decade... but it's far from down and out.

Comment: Re:As long as they get close it's a win (Score 1) 81

by DerekLyons (#48623425) Attached to: SpaceX To Attempt Falcon 9 Landing On Autonomous Spaceport Drone Ship

A very negative point of view.

Only in the eyes of the completely clueless or the drooling fanboy (not there's much effective difference between the two) are facts "negative".
 

If you get it back in one or a few bits then it is a win over just just chucking it up there and knowing you have lost it (as most rockets do)

Since the goal is to recover it whole, no, getting back in 'a few bits' is not a win. It's a failure. That things can and will be learned from such a failure does not change this.

Comment: Re:Not a cargo ship (Score 3, Interesting) 113

by DerekLyons (#48619665) Attached to: New Cargo Ship Is 488 Meters Long

Once again, when not using made up numbers, Green energies are the same.

Which is a very odd claim - since you produce no numbers whatsoever for "green" energy.

And you forget that natural gas isn't just a source of BTU's - it's also a major feedstock for a variety of industrial processes. (A significant portion of "oil derived" plastics are actually derived from natural gas.)

Comment: Re:As long as they get close it's a win (Score 1) 81

by DerekLyons (#48619545) Attached to: SpaceX To Attempt Falcon 9 Landing On Autonomous Spaceport Drone Ship

No, I missed the quoting the part that was (more-or-less, mostly less) correct. The parts I quoted were parts that you were wildly incorrect on, as there's considerable distance between what has been tested, and what they are testing. Even so, you're still wrong. Miss the target, by even a little bit, and it's a loss. Land hard and lose the vehicle (not due to sea state) and it's a loss. Tip over and lose the vehicle and damage or lose the barge (not due to sea state), and it's a loss.

So yes, it does matter if they miss, it does matter if they land hard or tip over - because the whole goal of the test is to demonstrate a successful pinpoint landing. You don't really seem to grasp what's being tested here and why.

Comment: TANSTAAFL (Score 1) 81

by DerekLyons (#48618497) Attached to: SpaceX To Attempt Falcon 9 Landing On Autonomous Spaceport Drone Ship

However, the cost of not having to rebuild the rocket every time is much more significant. Even if they can only reuse it a few times, that's a lot of production cost being saved.

The money saved by not having to produce a new vehicle is offset by the money spent on fixed infrastructure and on recovering and refurbishing the vehicle for the next flight. Airline travel is as a cheap as it is because they've gotten between-flights maintenance down to essentially zero (basically only emergent work) - the expensive refurbishment and refitting occurs at intervals of months to years. (And the amortized costs of the facilities for doing so are spread over a large number of aircraft and a very large number of flights.) The Shuttle was expensive as it was because between-flights maintenance costs were very high. (And the amortized costs of the infrastructure were spread over a very small number of vehicles and small number of flights.)
 
So, if a first stage (new-in-box) costs $x million and refurbishment costs $.9x million (including the amortized portion of the fixed costs), then it'll have to fly ten times just to break even. The break even point calculation is very sensitive to flight rate, flight interval, and the number of vehicles in the fleet. The hope is, over a long time frame, to reach civil aviation levels... but there's a long way to go between here and there. (Particularly in light of the low flight rate of F9 launches that have sufficient spare payload capacity to allow them to be recovered.)

Comment: Re:As long as they get close it's a win (Score 2) 81

by DerekLyons (#48618363) Attached to: SpaceX To Attempt Falcon 9 Landing On Autonomous Spaceport Drone Ship

If they can show over a couple attempts that they get close to the target then they can move to doing this over land. They have already proven they can do this in Texas many times.

There's a reason why they're flying all these attempts over water - they haven't done it in Texas even so much as once. The flights in Texas have been "take off, go a short distance up, then land more-or-less right back where you started" - which isn't the difficult part (so far as flight control is concerned, it's more of an engine control problem) as small errors have no time to propagate. The difficult part (from the flight control POV and the reason they are testing on a barge) is the boostback and retro burns, where even small errors in attitude and delta V propagate into significant errors by the time you hit your hovering gates (and is thus an engine control *and* a flight control problem). Another issue, also not tested in Texas, is the aerodynamics and flight dynamics of the returning stage (especially in the high speed regime), and indeed these issues caused a problem on the first attempt.

So no, coming close isn't a win. They're going to have to demonstrate pinpoint recovery a number of times before anyone is going to let them even consider attempting it over land.

Comment: Stupid conclusion in TFA (Score 1) 594

by DerekLyons (#48603233) Attached to: Waze Causing Anger Among LA Residents

From TFA:

So while a shortcut down a sleepy street might not be a problem in a place like Des Moines or even Detroit, it's a different story in a city that last year was again ranked No. 1 for the nation's most time-consuming traffic jams.

Why wouldn't it be a problem for those of use not living in Trendville? It was a hell of a problem here in a town much smaller (37k) than either Detroit (681k) or Des Moines (203k) where cars would speed (during non rush hour) down a neighborhood street or pack it bumper to bumper (during rush hour) to cut around a stop light - especially when the elementary school one more street over was letting out and the area was filled with kids walking home. It finally took a kid getting hit (though thankfully not seriously injured) before the city stopped "studying the problem" and got around to blocking one end of the street.

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